It's an end of an era in Havana. On Wednesday, Cuba's National Assembly convened a session that will culminate in President Raúl Castro stepping down from his post in favor of his first vice president, Miguel Diaz-Canel. The move sets the stage for a startling reality: Diaz-Canel will become the first non-Castro to lead the Caribbean nation since Marxist revolutionaries swept to power almost six decades ago.

Castro, 86, will remain head of the country's Communist Party, although he is in the twilight of his career. His brother Fidel Castro, architect of the regime that has withstood decades of American blockade, stepped down in his favor in 2008 and died two years ago. And while the ascension of Diaz-Canel — a handpicked successor plucked from the ranks of the Communist leadership — has been telegraphed for months, it still presents a dramatic inflection point.

“For me, not having a Fidel or Raul, it’s almost impossible to conceive of,” Giraldo Baez, a 78-year-old former factory worker, told my colleague Anthony Faiola in Havana. “It’s almost out of my realm of understanding. But even as they go, I feel we still need to follow their ideas.”

Among the hard-bitten Cuban diaspora in the United States, there is little reason to cheer. “Today is a day when the Castro dynasty is appointing a new monarch to commit even more crimes,” said Miguel Saavedra, president of a group of Cuban exiles in Miami. “The future ahead for the Cuban people is tragic and pathetic while Castro is still in power.”

Miguel Diaz-Canel stands in line at an election of candidates for the national and provincial assemblies, in Santa Clara, Cuba, March 11. (Alejandro Ernesto/Reuters)

That's a line of argument shared by many Republicans in Washington and hawks in the Trump administration. In the space of a year, President Trump has set about reversing the landmark steps toward normalization with Cuba that President Barack Obama had set in motion. Obama had visited Cuba in 2016 and delivered a speech watched by millions. He was followed by myriad U.S. politicians, fashion icons, Wall Street CEOs and business executives, and thousands of tourists — whose arrival all buoyed Cuba's fledgling private sector.

“These steps loudly signaled the return of Florida’s pro-embargo faction, led by Senator Marco Rubio, at the helm of U.S.-Cuba policy,” wrote Ted Piccone of the Brookings Institution. “Now, with the appointment of the more hardline John Bolton and Mike Pompeo to top national security positions, we should expect the White House to double down on its first year’s embrace of punitive regime change.”

This uncompromising position has had a chilling effect within Cuba. It also probably offered relief to hard-liners within the Communist Party who were wary of the forces of liberalization that Obama's opening could unleash. “Cuba and the United States can cooperate and live side by side, respecting their differences,” Castro said last year. “But no one should expect that for this, one should have to make concessions inherent to one’s sovereignty and independence.”

The Cuban government has since stalled its efforts to grow the private sector. “Cuban officials last year put a temporary halt on issuing new licenses for private businesses, arguing that time was needed to ensure that the island’s new crop of entrepreneurs was paying taxes and operating within the law,” Faiola explained. “The freeze was seen as motivated by influential party officials still highly skeptical of change.”

Diaz-Canel, 57, is from a generation of Cuban politicos who never manned the guerrilla front lines alongside Fidel, Che Guevara or other figures from the halcyon days of revolution. Instead, he cut his political teeth in the 1990s as Cuba reckoned with the economic catastrophe that followed the collapse of the Soviet Union. He is seen as something of a pragmatist and a proponent of new technology. But his assumption of the presidency is also a mark of his closeness to the prevailing order.

Diaz-Canel faces pressure to bolster Cuba's flagging economy, which can no longer count on being buttressed by Venezuela's petro-wealth. He may have to spearhead monetary reform and push for further foreign investment, calibrating the imperative for loosening up against the fears of the Communist establishment.

Raúl Castro and Diaz-Canel chat during a session of the National Assembly in 2016. (AFP via www.cubadebate.cu)

Obama and his lieutenants believed the United States could help coax along these changes. But analysts argue that Trump's unvarnished hostility to Havana narrows the scope of Diaz-Canel's possible actions. “The United States and other outside actors will not determine the nature or the timing of these changes,” Marguerite Jimenez wrote in Foreign Affairs last month. “They can, however, create a climate in which reform is easier. Strategies of U.S. engagement that recognize Cuban sovereignty and resist calling for regime change will reduce the risks to Díaz-Canel of undertaking more significant changes.”

Other foreign powers — most notably China and Russia — have stepped in, restructuring or forgiving tens of billions of dollars in Cuban debt, while investing in various sectors of the Cuban economy. China is Cuba's biggest trading partner, accounting for $1.8 billion in exports to the island in 2017, according to Jimenez. In the same year, Russian exports to Cuba, including shipments of oil, increased by 81 percent.

“Trump’s bullying,” the New Yorker's Jon Lee Anderson concluded, “only makes it more likely that the Cubans, with or without a Castro, will do what they have done for the past fifty-nine years: exhibit stubborn pride and, if necessary, forge tactical alliances with any of America’s geostrategic foes who might be willing to watch their back.”